Insulating Material

ABSTRACT

An insulating material for storing contents, such as ice. The material can be in a blanket form or can be formed into a container, such as a bag. The material comprises an inner layer of air cellular sheet material, an outer layer of air cellular sheet material, and a barrier sheet between the inner and outer layers of air cellular sheet material. A container can be provided with a sealable opening for inserting and removing contents from the container. The air cellular sheet material may comprise entrapped air cells or bubbles. The barrier sheet may be formed from paper such as “Kraft” paper. The sealable opening can comprise a closure or seal, such as a plastic zip fastener or a thistle cloth hook and loop fastener, where the opening may be resealed following removal of contents from the container.

RELATED APPLICATIONS

This patent application is a continuation of and claims priority to International Patent Application No. PCT/IB2010/003401 entitled “Insulating Material” and filed Dec. 8, 2010, which claims priority to U.S. patent application Ser. No. 12/835,318 entitled “Insulated Bag for Ice Storage” and filed Jul. 13, 2010. The complete disclosure of each of the above-identified applications is hereby fully incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to an insulating material, and, more particularly, to an insulating laminate material.

BACKGROUND

When persons are picnicking or having a beach party, it is desirable to provide insulated containers for the storage and transportation of ice, in particular for the storage and transportation of ice cubes (or other shaped ice pieces) used to cool drinks. Ideally, the insulated containers should be inexpensive and portable, as well as providing excellent thermal insulation to minimize the melting of the stored ice even when the container is held in warm ambient conditions for extended periods.

Various picnic coolers are known for storing and transporting ice. These consist of a rigid, thermally insulating body and a rigid, thermally insulating lid. Such picnic coolers are quite heavy and bulky. It is also known to use vacuum flasks for storing and transporting ice, but there are cost and weight disadvantages with this solution. WO-A-2006126899 describes a beverage pack that comprises a bladder with at least one strap that is integral to the pack to enable the pack to be carried on a user's back. The pack may include an area of insulation, such as bubble type wrap or any other appropriate insulating material, on at least part of it. The pack may also include a reflective panel, such as silver type plastic, on its front panel to keep the beverage within the pack cold and to reflect sunlight. The pack includes a non-toxic drinking hose that is sealed within pack. However, this pack is not suitable for carrying ice.

SUMMARY

The present invention provides an insulating material. The material can be provided in blanket form or can be formed into a container. The container is suitable for storing ice or other cold or hot contents to help maintain the temperature of those contents for a period of time. The material comprises an inner layer of air cellular sheet material, an outer layer of air cellular sheet material, and a barrier sheet between the inner and outer layers of air cellular sheet material. A vapor barrier can be included adjacent to the inner layer. The outer layer can be wrapped around the barrier layer, thereby allowing air between at least a portion of the outer layer and the barrier layer. According to one aspect, the material can be formed into a bag form and can be provided with a sealable opening for inserting and removing items from the bag.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a plan view of an insulated storage bag according to an exemplary embodiment.

FIG. 2 shows a longitudinal cross section through the insulated storage bag of FIG. 1 when empty (FIG. 2A) and when filled with ice cubes (FIG. 2B) according to an exemplary embodiment.

FIG. 3 shows a detailed cross-sectional view of part of the insulating laminate in the embodiments of FIGS. 1 and 2 according to an exemplary embodiment.

FIG. 4 shows a detailed cross-sectional view of the sealing region of FIG. 2 according to an exemplary first embodiment (FIG. 4A) and an exemplary second embodiment (FIG. 4B).

FIG. 5 shows a plan view of a further exemplary embodiment in which a bag according to the embodiments of FIGS. 1-4 is inserted into an outer, carrier bag having handles.

FIG. 6 shows a detailed cross-sectional view of part of the insulating laminate in the embodiments of FIGS. 1 and 2 according to an exemplary embodiment.

FIG. 7 shows a detailed cross-sectional view of the sealing region of FIG. 2 according to an exemplary first embodiment (FIG. 7A) and an exemplary second embodiment (FIG. 7B).

DESCRIPTION OF EXEMPLARY EMBODIMENTS

The term “bag” refers to a collapsible container formed substantially or completely from flexible sheet material. The bag according to the invention is formed substantially or completely from a heat insulating laminate comprising or consisting essentially of an inner layer of air cellular sheet material, an outer layer of air cellular sheet material, and a barrier sheet between the inner and outer layers of air cellular sheet material.

The term “air cellular sheet material” refers to thermoplastic sheet material containing a regular, two-dimensional array of entrapped air cells. Such materials are widely used for shock-resistant packaging of goods, and are available for example from Sealed Air Corporation under the Registered Trade Mark BUBBLE WRAP. Suitably, the entrapped air cells are of uniform size and shape, for example they may be substantially hemispherical. Suitably, the entrapped air cells have a volume of from about 0.05 cm³ to about 4 cm³, for example from about 0.2 cm³ to about 1 cm³. Suitably, the maximum thickness of the air cellular sheet material is from about 3 mm to about 25 mm, for example from about 5 mm to about 1 cm. Suitably, the entrapped air cells are arranged in a substantially close-packed array. Suitably, the entrapped air cells occupy at least about 50% of the area of the cellular sheet material, for example at least about 75% of the area of the cellular sheet material, in plan view. In certain embodiments, the entrapped air cells form an array of protuberances on one side of the cellular sheet, the other side of the sheet being substantially flat. In these embodiments, the non-flat sides of the sheets suitably abut the barrier sheet, whereby the interior and exterior surfaces of the insulating laminate are substantially flat.

The air cellular sheet material is suitably formed from a thermoplastic, such as polyethylene. The edges of this material are suitably heat-welded, at least for the inner layer, to form a watertight enclosure for the ice.

The barrier sheet is intercalated between the two sheets of air cellular sheet material in the insulating laminate. The barrier sheet is suitably formed from a substantially continuous, flexible sheet material such as a thermoplastic film or paper. Suitably, the barrier sheet is formed from paper, for example from “Kraft” paper. The barrier layer reduces convective heat transfer and may also serve as a light barrier. The barrier layer can also be used to regulate the stiffness of the insulating laminate for optimum stiffness of the bag, since the air cellular sheet materials alone may be insufficiently rigid. The ice bag according to the present invention further comprises a sealable opening for inserting and removing ice or other contents (hot or cold) from the bag. The term “sealable opening” refers to an opening that can be sealed after filling of the bag, and opened subsequently to remove the ice from the bag. Suitably, the opening is readily resealable following removal of part of the contents of the bag. Suitably, the opening extends partially or completely along an edge of the bag.

The opening is suitably adapted to be repeatedly opened and closed by closure/sealing means suitably formed from a rib extending across one panel of the inner air cellular sheets below the opening of the bag and inter-engaging in a groove formed between, and therefore defined by, two ribs extending across the other panel and also below the opening of the bag. Two parallel extending ribs on either sides of the rib which engages within the groove serve to capture the ribs within the defined groove. The ribs and grooves are shaped and dimensioned so that the rib fits tightly within its associated groove and the ribs defining the associated groove deform to allow the rib to enter and to be captured within its associated groove. The bag is opened by gripping the free edges of the panel at the opening of the bag and pulling the panels apart with the rib disengaging from its associated groove thereby allowing access to the interior of the bag to receive or retrieve the ice. To close or reseal the opening to the bag one end of the rib is pressed by thumb and finger pressure into the adjacent end of the associated groove with the thumb or finger under pressure being subsequently drawn along the length of the rib and groove arrangement to progressively introduce the rib into its associated groove to be tightly received therein and whereby to seal the opening of the bag. Alternatively, a fastener tab (zipper) may be drawn along the length of the rib and groove to press them together. The opening of the bag can be repeatedly opened and closed as required, with the closure process being analogous to that accomplished by a zipper and thus the term “zipper” is sometimes used to describe such reclosable bags. Reclosable plastic bag fasteners of this type are available, for example, under the Registered Trade Marks ZIPLOC (S.C. Johnson & Co.) and MINIGRIP (the Minigrip Company).

Alternatively or additionally, the resealable fastener on the opening of the bag may comprise thistle cloth, for example the cloth available under the registered trade mark VELCRO.

The dimensions of the ice bag according to the present invention are suitably from about 10 cm to 50 cm×10 cm to 50 cm in plan view. The storage capacity of the bag is suitably from about 100 g to about 10 kg of ice, for example from about 500 g to about 2 kg of ice. Suitably, the storage bag according to the present invention contains from about 100 g to about 10 kg of ice. The ice is suitably in the form of pieces, such as cubes. For example, at least about 75% of the ice by weight is suitably present in the form of ice cubes or other ice pieces each having a weight in the range of from about 1 g to about 100 g, for example about 5 g to about 50 g.

The insulated storage bags according to the present invention may conveniently be made by starting from a commercially available padded envelopes having an air cellular lining layer and an outer layer of “Kraft” paper. The insulated storage bags are produced by wrapping a further air cellular insulating layer around the envelope. A suitable plastic zip fastener may be attached across the opening of the envelope. The resulting assembly is optionally inserted into a carrier bag having handles. A person having ordinary skill in the art and the benefit of this disclosure will understand that the insulating material can be used in its layered form as a “blanket” type material or can be formed into any suitable shape for a container, such as the bag form described previously.

An exemplary embodiment of the insulated storage bag according to the present invention will now be described further, by way of example, with reference to the accompanying drawings.

Referring to the drawings, the insulated storage bag 1 according to the present invention is generally in the shape of an envelope formed from a sheet of insulating laminate 3 that is folded about a bottom edge 2 to define front and back faces, the faces being thermally bonded together along side edges 4, 5. The top edge of the envelope is provided with a resealable opening 6 that can be opened and resealed to admit or remove ice or other contents from the bag. The sheet of insulating laminate comprises an inner layer 8 of air cellular sheet material, a barrier sheet 9 of “Kraft” paper, and an outer layer of air cellular sheet material 10. In this embodiment, the air cellular sheet materials are BUBBLE WRAP having an array of substantially hemispherical air cells, each of a diameter about 10 mm. The air cells define an array of protuberances on a first, non-flat side of the air cellular sheet material, the other side of the air cellular sheet material being substantially flat. The inner and outer layers of air cellular sheet material are configured so that the non-flat faces thereof abut the barrier sheet and the flat surfaces form the outer surfaces of the laminate.

The resealable opening 6 in the top edge of the envelope may be closed by a ZIPLOC® type plastic zip fastener 12, as shown in FIGS. 4A and 7A. According to the alternative embodiments shown in FIGS. 4B and 7B, the resealable opening 6 is sealed by complementary strips 13, 14 of thistle cloth bonded to the inner surface of the laminate along the top edge.

As also illustrated in the exemplary embodiment of FIG. 4B, the outer layer 10 may be wrapped around the barrier sheet 9 such that an air layer 17 exists between at least a portion of the outer layer 10 and the barrier sheet 9.

As further illustrated in FIG. 7, the outer layer 10 can be wrapped over the barrier sheet 9. This configuration, as described above with reference to FIG. 4B, can include the air layer 17 between at least a portion of the outer layer 10 and the barrier sheet 9. The outer layer 10 can be sealed to the barrier sheet 9 (or the closure mechanism, such as the fastener 12 or the thistle cloth strips 13, 14) at the entrance to the opening 6, thereby sealing the air layer 17 between the outer layer 10 and the barrier sheet 9.

In the embodiment of FIG. 5, the bag 1 of insulating laminate is enclosed in a plastic carrier bag 15 of polyethylene or similar material having handles 16 for carrying.

In use, the bag is filled with ice cubes, similar ice pieces, or other contents as shown in FIG. 2B, and is then sealed with the fastener 6. In an exemplary embodiment, the contents can be separated from the inner layer 8 via a vapor barrier (not shown). The vapor barrier can be formed of, for example, a foil material, a thermoplastic material, or other suitable vapor barrier. The bag can then be opened at any time to remove the contents from the bag. The insulating material according to the present invention can provide advantages of excellent thermal insulation, low cost, light weight, and the ability to collapse the insulating material after use for easy portability and storage. A further advantage of the collapsible bags is that they can be filled with more or less ice or other contents, according to need, without leaving a void space in the container formed from the material.

The barrier sheet 9 can be an insulating material, such as the “Kraft” paper described previously. The insulating material allows water vapors created by the hot-cold climate exchange to be moved away from the cold or heat sources without causing condensation or moisture build up on the insulating material, thus maintaining its structural and insulating integrity. The insulating material is comprised of a cellulose and fibrous structure that allows a conductive exchange between the hot and cold environment (sweating, breathing, and drying). The insulating material can repeatedly become wet and then dry at very fast rates without compromising the structural integrity, thus acting as a highly effective insulating barrier and maintaining, for example, a colder interior temperature of the insulated bag when containing cold contents for longer periods of time in warm or hot environments.

EXAMPLE

Two double layered bags of air cellular sheet material were each filled with one cup of ice cubes. One of the bags had the barrier sheet of insulating material interposed between the layers of air cellular sheet material; the other bag did not have the barrier sheet of insulating material. Both bags were placed in outdoors in direct sunlight at a temperature of 94°. The ice in the bag without the barrier sheet of insulating material began to melt immediately and completely melted within twenty minutes. The ice in the bag with the barrier sheet of insulating material did not show any signs of melting for the first ninety minutes and did not completely melt for a period of 6 hours and 22 minutes.

When a contained extreme cold material, such as ice, is exposed to an extreme hot environment, condensation is created, especially if the heat exposure is further intensified on the ice in a double-layered, air cellular sheet material container without the barrier sheet of insulating material. The condensation inside the container greatly contributes to the quickened melting of the ice in the container. When the exact same conditions are created and a barrier sheet of insulating material is added between the layers of the container, the melting time of the ice is extended significantly.

Although specific embodiments have been described above in detail, the description is merely for purposes of illustration. It should be appreciated, therefore, that many aspects described above are not intended as required or essential elements unless explicitly stated otherwise. Various modifications of, and equivalent features corresponding to, the disclosed aspects of the exemplary embodiments, in addition to those described above, can be made by a person of ordinary skill in the art, having the benefit of the present disclosure, without departing from the spirit and scope of the invention, the scope of which is to be accorded the broadest interpretation so as to encompass such modifications and equivalent structures. 

What is claimed is:
 1. An insulated container, comprising: an inner layer of air cellular sheet material that forms a compartment; an outer layer of air cellular sheet material disposed on a side of the inner layer that is opposite to the compartment formed by the inner layer; and an opaque layer between the inner and outer layers of air cellular sheet material.
 2. An insulated container according to claim 1, wherein the inner and outer layers of air cellular sheet material each comprise entrapped air cells having a volume of from about 0.05 cm³ to about 4 cm³ or from about 0.2 cm³ to about 1 cm³.
 3. An insulated container according to claim 1, wherein a maximum thickness of the air cellular sheet material of each of the inner and outer layers is from about 3 mm to about 25 mm or from about 5 mm to about 1 cm, and wherein the inner and outer layers of air cellular sheet material each comprise entrapped air cells arranged in a substantially close-packed array.
 4. An insulated container according to claim 1, wherein the inner and outer layers of air cellular sheet material each comprise entrapped air cells that form an array of protuberances on a first side of the inner and outer layers, wherein a second side of each of the inner and outer layers is substantially flat, and wherein the first sides of the inner and outer layers abut the opaque layer.
 5. An insulated container according to claim 1, wherein the opaque layer is formed from a paper material.
 6. An insulated container according to claim 1, further comprising a sealable opening that allows access to the compartment of the container.
 7. An insulated container according to claim 6, wherein the sealable opening is resealable.
 8. An insulated container according to claim 1, further comprising a carrier layer that surrounds at least a portion of the outer layer, the carrier layer comprising a handle.
 9. An insulated container according to claim 1, wherein the storage capacity of the container is from about 100 g to about 10 kg or from about 500 g to about 2 kg.
 10. An insulated container according to claim 1, further comprising from about 100 g to about 10 kg or from about 500 g to about 2 kg disposed within the container.
 11. An insulated container according to claim 1, wherein the container is a collapsible container.
 12. An insulated container according to claim 1, wherein the container is a bag.
 13. An insulated container according to claim 1, wherein an air layer exists between at least a portion of the outer layer and the opaque layer.
 14. An insulated container according to claim 1, further comprising a vapor barrier disposed adjacent to the inner layer.
 15. An insulating laminate, comprising: a first layer of air cellular sheet material; a second layer of air cellular sheet material; and a third layer of opaque material disposed between the first and second layers.
 16. An insulating laminate according to claim 15, wherein the first and second layers each comprise a plurality of entrapped air cells.
 17. An insulating laminate according to claim 15, wherein the first and second layers each comprise a plurality of entrapped air cells arranged in a substantially close-packed array.
 18. An insulating laminate according to claim 15, wherein the first and second layers each comprise entrapped air cells that form an array of protuberances on a first side of each of the first and second layers, and wherein the first sides of the first and second layers abut the third layer.
 19. An insulating laminate according to claim 18, wherein a second side of each of the first and second layers is substantially flat.
 20. An insulating laminate according to claim 15, wherein the third layer is formed from a paper material.
 21. An insulating laminate according to claim 15, wherein the laminate is formed into a container.
 22. An insulating laminate according to claim 21, further comprising a sealable opening that allows access to an interior of the container.
 23. An insulating laminate according to claim 22, wherein the opening is resealable.
 24. An insulating laminate according to claim 21, further comprising a handle coupled to the container.
 25. An insulating laminate according to claim 21, wherein the container is a bag.
 26. An insulated container according to claim 21, wherein the container is a collapsible container.
 27. An insulating laminate according to claim 21, further comprising a fourth layer that encompasses at least a portion of the container.
 28. An insulating laminate according to claim 27, wherein the fourth layer comprises a handle.
 29. An insulating laminate according to claim 15, wherein the laminate forms a heat insulating material.
 30. An insulated container according to claim 15, wherein an air layer exists between at least a portion of the outer layer and the opaque layer.
 31. An insulated container according to claim 15, further comprising a vapor barrier disposed adjacent to the inner layer. 